My answer is, "speak for yourself, old man".:)
I'll even go one step further and say I pity people who have no idea what to do with themselves if they are not working in a real job or run their own business.
Is that really all you think there is to life?
Why the hell are people so afraid to let go of one part of their lives and move on? I understand what it is to be a driven individual with a thriving business or a comfortable, well set up career and decide to continue on because you can and you enjoy it.
If you are passionate and fulfilled and have something to give to society by staying in your field, more power to you!
But, let's get real, the majority of the people stay in their job, because they have to or they have no clue what else to do. They are afraid of change and/or afraid their money might run out or afraid to suddenly be home with a life partner they should have divorced years ago.
As far as the MMM way of life, just look at Mr. MM - he retired from the working world and then re-entered on his own terms. He isn't bored with his life he continues the journey, exploring different things. That is a quality early retirement!
We are all wired differently.
I've easily crammed five lifetimes in this one life and I was damn well ready to let go and relax. Three years in, there are still tons of things I want to do and there is still so much to see and experience, but I can assure you of one thing the (real:) working world is not one of them. Thanks, but no thanks!